@article{DE_1984_20_10_a25,
     author = {A. V. Makhorkin},
     title = {The normal form on an invariant surface of a completely integrable {Pfaffian} system},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1824--1827},
     publisher = {mathdoc},
     volume = {20},
     number = {10},
     year = {1984},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1984_20_10_a25/}
}